Metal-organic frameworks on 3D interconnected macroporous sponge foams for large-scale water decontamination:A mini review

Water pollution caused by global population growth,urban expansion and industrialization development is one of the urgent issues that need to be addressed in the 21st century.Up to now,it was challenging for metal-organic frameworks(MOFs)to be used in the actual water treatment due to that the powder MOFs suffered from difficult reuse,poor water stability and easy corrosion.It is an effective strategy to immobilize MOFs powder onto porous sponge foam carriers for accomplishing large flux,facile recycling,easy processing water treatment setups.In this review article,the fabrication approaches and applications of different MOFs/sponge composites were highlighted,in which the fluorescence detection of pollutants,adsorption and separation of pollutants,catalytic reduction and oxidation of pollutants were included.Finally,the future challenges and opportunities of MOF/sponge for water treatment are proposed,aiming to provide in-depth guidance for the future design and manufacture of the immobilized MOFs onto sponge foams.

Intensifying electrified flow-through water treatment technologies via local environment modification

Removing high-risk and persistent contaminants from water is challenging,because they typically exist at low concentrations in complex water matrices.Electrified flow-through technologies are viable to overcome the limitations induced by mass transport for efficient contaminant removal.Modifying the local environment of the flow-through electrodes offers opportunities to further improve the reaction kinetics and selectivity for achieving near-complete removal of these contaminants from water.Here,we present state-of-the-art local environment modification approaches that can be incorporated into electrified flow-through technologies to intensify water treatment.We first show methods of nanospace incorporation,local geometry adjustment,and microporous structure optimization that can induce spatial confinement,enhanced local electric field,and microperiodic vortex,respectively,for local environment modification.We then discuss why local environment modification can complement the flow-through electrodes for improving the reaction rate and selectivity.Finally,we outline appropriate scenarios of intensifying electrified flow-through technologies through local environment modification for fit-for-purpose water treatment applications.

Selective activation of peroxymonosulfate to singlet oxygen by engineering oxygen vacancy defects in Ti_(3)CNT_(x) MXene for effective removal of micropollutants in water

Defect engineering is an effective strategy to boost the catalytic activity of MXene towards heterogeneous peroxymonosulfate(PMS)activation for water decontamination.Herein,we developed a facile approach to fine-tune the generation of oxygen vacancies(OVs)on Ti_(3)CNT_(x)crystals by Ce-doping(Ce-Ti_(3)CNT_(x))with the aim of mediating PMS activation for the degradation of micropollutants in water.By varying the dopant content,the OV concentrations of Ti_(3)CNT_(x)could be varied to enable the activation of PMS to almost 100%singlet oxygen(1O2),and hence the effective degradation of sulfamethoxazole(SMX,a model micropollutant).Various advanced characterization techniques were employed to obtain detailed information on the microstructure,morphology,and defect states of the catalysts.The experimental results showed that SMX removal was proportional to the OVs level.Density functional theory(DFT)models demonstrated that,in contrast to pristine Ti_(3)CNT_(x),the OVs on 10%CeTi_(3)CNT_(x)could adsorb the terminal O of PMS,which facilitated the formation of SO_(5)•−as well as the generation of 1O2.We further loaded the optimized catalysts onto a polytetrafluoroethylene microfiltration membrane and also demonstrated the efficient removal of SMX from water using a convection-enhanced mass transport flowthrough configuration.This study provides new insights into the effective removal of micropollutants from water by integrating state-of-the-art defect engineering,advanced oxidation,and microfiltration techniques.